1. Field of the Invention
The present invention relates to an airbag and an airbag device provided with the airbag, that are configured to control a flow of an inflation gas to be supplied to the airbag, and that are capable of preventing an occurrence of an undesirable circumstance such as hitting of the airbag against somewhere under the jaw of the occupant and safely buffering and supporting an occupant, even in a case where the occupant is seated in proximity to an instrument panel.
2. Description of the Related Art
At present, as a safety device configured to protect an occupant in a case where a vehicle such as a motor vehicle collides with any obstacle, an airbag device is equipped in front of a driver's seat and a passenger's seat. In general, when a vehicle collides with any obstacle and then is subject to a significant impact, this airbag device detects such an impact, generates a high pressure gas from an inflator, and introduces the gas into the airbag, thereby momentarily expanding and inflating the airbag. In this manner, an occupant is buffered and supported by the airbag, and an impact force which is applied to a human body can be significantly mitigated; and therefore, the safety of the occupant at the time of collision is ensured.
Conventionally, in an airbag device for passenger's seat, an airbag is retracted and housed in a case which is disposed inside of an instrument panel, and is arranged so as to protrude an opening on a front face side of the instrument panel at the time of the inflow of an inflation gas and then expand and inflate at a rear side of a vehicle.
Accordingly, in the airbag of such type, it has been a common routine to expand and inflate the airbag so as to be moved to the rear side of the vehicle in a state in which movement prior to the completion of the expansion and inflation at each portion at a wall portion on the occupant's side is restrained to its required minimum while a wide face on which the wall portion on the occupant's side is taken along a direction which is orthogonal to a direction in which the airbag faces the occupant (for example, a rear side of the vehicle, and hereinafter, this direction is referred to as an occupant's side direction) is ensured from a state prior to the completion of the expansion and inflation of the airbag by taking an account into a folded shape of the airbag (reference should be made to Japanese Patent No. 4465873) or disposing a rectification cloth in the airbag (reference should be made to Japanese Unexamined Patent Application Publication No. 11-278192), etc.
However, in the airbag device of Japanese Patent No. 4465873 that is provided in such a manner that the airbag is first folded in a vertical direction (folded laterally) and then folded in a transverse direction (folded longitudinally) or in the airbag device of Japanese Unexamined Patent Application Publication No. 11-278192 that is provided in such a manner that a rectification cloth is provided inside of the airbag so as to diverge the hot air or high pressure gas that is blown out to the inside of the airbag, in a vertical direction of the airbag by the rectification cloth, there has been a need to make a contrivance for the layout at the periphery of a front sheet of a vehicle including the disposition or mode of the instrument panel, or alternatively, to employ a specific control device or a specific structure in order to appropriately protect the occupant irrespective of whatsoever posture seated by the occupant may be when the airbag inflates and expands.
As a result, a design of the vehicle or disposition of a variety of parts is limited, and there has been a case in which a degree of freedom in its related design lowers or a case in which its related manufacturing costs increase. Thus, there has been a desire to develop an airbag device which is capable of speedily inflating and expanding an airbag in a direction which is orthogonal to the occupant's side direction with a simpler structure.